Selling cigarettes in unbranded packs seems to make tobacco less appealing and encourages smokers to quit, suggests a study.
The work comes from Australia – the first country to introduce plain packaging.
The BMJ Open research looked at the impact of the policy on 536 smokers in the state of Victoria.
The findings come days after ministers were criticised for putting on hold a plan to impose plain packs in England.
Downing Street denied the Tories’ election strategist, Lynton Crosby, had been responsible for the delay to plain packaging.
Mr Crosby’s links with alcohol and tobacco companies have been called into question by some MPs.
Defending the decision to delay, Health Secretary Jeremy Hunt said the government wanted more time to see how the policy had worked in Australia.
The BMJ Open study gives an early indication of precisely this.
Researchers polled a sample of smokers during November 2012 when plain packs were already available in the run up to the country-wide introduction of the legislation.
Almost three out of four (72.3%) were smoking cigarettes from plain packs while the remainder (27.7%) were still using branded packs with smaller health warnings.
Compared with branded pack smokers, smokers using plain packs were 66% more likely to think their cigarettes were poorer quality than a year ago and they were 70% more likely to say they found them less satisfying.
They were also 81% more likely to have thought about quitting at least once a day during the previous week.
And plain pack smokers were 51% more likely to back the plain pack policy than were brand pack smokers.
Simon Clark, director of the smokers’ group Forest, said the study offered “no credible evidence” to suggest that plain packaging will reduce smoking rates.
“The research, which was carried out in November 2012, before plain packaging was introduced, is based on highly subjective responses to questions about the perceived quality of cigarettes and the satisfaction consumers derive from smoking cigarettes sold in standard packs.
“There is no evidence that the sale or consumption of cigarettes has fallen in Australia since plain packs were introduced in December.”
Kate Alley of Cancer Research UK disagreed, saying: “When cigarettes aren’t disguised by flashy packaging and carefully crafted branding, smokers see them for what they are – a lethal product which kills half of its long term users.”
She said ministers should “stop stalling” and introduce standardised packs in the UK as soon as possible, adding that 85% of the British public wanted government action to reduce the number of children who smoke.
Simon Gillespie, of the British Heart Foundation, said: “These are clear-cut findings about how existing smokers have reacted to the changes in Australia. Westminster has absolutely no excuse for delaying legislation to introduce standardised packaging.”
A Department of Health spokeswoman said: “We take very seriously the potential for standardised packaging to reduce smoking rates, but in light of the differing views, we have decided to wait until the emerging impact of the decision in Australia can be measured, and then we will make a decision in England.
“This decision is an important one and whilst we keep it under review, we’ll be continuing to implement our existing plan to reduce smoking rates through ending the display of tobacco in all shops, running national behaviour change campaigns to encourage smokers to quit and through supporting local authorities to provide effective stop smoking services.”
“When cigarettes aren’t disguised by flashy packaging and carefully crafted branding, smokers see them for what they are – a lethal product which kills half of its long term users”
Kate AlleyCancer Research UK’s tobacco policy manager